S1 chapter 5 - probability

In this chapter you will learn how to:

• define common terms in probability
• solve probability problems
• use set notation and Venn diagrams to solve probability problems with multiple events
• use formulae to find probabilities
• draw tree diagrams to solve problems involving conditional probability
• distinguish and identify mutually exclusive and independent events
• use combinatorics to find the number of arrangements of items

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S1 § 5.1 - probability vocabulary

Prior knowledge:

• You have already met the concept of probability and know that probabilities are values used to describe the chance of an event
• You can work with fractions, decimals and percentages

After learning the material in this section you will learn:

• The definitions of experiment, outcome, event and sample space.
• The conventional notation P(E) to give the probablility of some event called 'E'
• That, for n equally likely outcomes with k of these in the event E, P(E) = k/n
• That for impossible events, P(E) = 0
• That for certain events, P(E) = 1
• For all other events 0 < P(E) < 1

Examples:

S1 Ex 5A

• S1 Exercise 5A worked solutions:

• Questions similar to this exercise:

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S1 § 5.2 - Venn diagrams

Prior knowledge:

• a basic understanding of probability from S1 § 5.1

After learning the material in this section you will learn:

• what a Venn diagram looks like
• the set notation for union and intersection and the use of E' for not E

Examples:

S1 Ex 5B

• S1 Exercise 5B worked solutions:

• Questions similar to this exercise:

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==S1 § 5.3 - using formulae
Prior knowledge:

• You understand Venn diagrams from S1 § 5.2 and can use it to identify why the formulae below are true

After learning the material in this section you will learn:

• the addition rule:

$P(A \cup B) = P(A) + P(B) - P(A \cap B)$

Examples:

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S1 Exercise 5A

• S1 Exercise 5A worked solutions:

• Questions similar to this exercise:

S1 § 5.1 - probability vocabulary

Prior knowledge:

• You have already met the concept of probability and know that probabilities are values used to describe the chance of an event
• You can work with fractions, decimals and percentages

After learning the material in this section you will learn:

• The definitions of experiment, outcome, event and sample space.
• The conventional notation P(E) to give the probablility of some event called 'E'
• That, for n equally likely outcomes with k of these in the event E, P(E) = k/n
• That for impossible events, P(E) = 0
• That for certain events, P(E) = 1
• For all other events 0 < P(E) < 1

Examples:

S1 Exercise 5A

• S1 Exercise 5A worked solutions:

• Questions similar to this exercise:

S1 section 5.1 - probability vocabulary

Prior knowledge:

• You have already met the concept of probability and know that probabilities are values used to describe the chance of an event
• You can work with fractions, decimals and percentages

After learning the material in this section you will learn:

• The definitions of experiment, outcome, event and sample space.
• The conventional notation P(E) to give the probablility of some event called 'E'
• That, for n equally likely outcomes with k of these in the event E, P(E) = k/n
• That for impossible events, P(E) = 0
• That for certain events, P(E) = 1
• For all other events 0 < P(E) < 1

Examples:

S1 Exercise 5A

• S1 Exercise 5A worked solutions:

• Questions similar to this exercise: